Tool-retaining device



Dec. 4,1922; 1,693,872

- E. H. SHAFF TOOL RETAINING DEVICE Filed May 11, 1925 Patented Dec. 4, 1928.

A UNITED STATES PATENTI'OFF 1,693,872 ICE. t

ERNEST H. SHAFF, OF GRAND HAVEN, MICHIGAN. ASSIGNOR TO YWIIJLIAM H. KELLER, i INCL, OF GRAND HAVEN, MICE-IIGAN, A CORPORATION OF MICHIGAN.

TOOL-RETAINING DEVICE.

Application filed May 11, 1925.

This invention relatesgenerally to pneumatic hammers and the like and has partic ular reference to means employed for retain However, when it is desirable to remove the tool the same should be readily removed with out any difficulty.

The object of this invention is to provide a retainer for a rivet set or like tool, which serves to prevent the accidental discharge of the tool from the hammer as the latter is vention will be apparent from the descrip tion of the exemp ary embodiment of the invention as illustrated in the accompanying drawings, in which 7 Figure 1 is a cross sectional view of the nose of a pneumatic hammer equipped with the retaining device.

Fig. 2 is a side view in elevation of the device shown in Fig. 1 with the device laterally offset to permit removal of the tool.

Fig. 3 is across section "taken on the line 3-3 of Fig. 1. v

Fig. 4 is a view in perspective of theretaining clip.

It will be understood that the particular embodiment of the'invention shown in the accompanying drawings is given by way of illustration and explanation of the nature of the invention and that it is not to be construed as a limitation thereof to the precise construction illustrated. It is further to be understood that such other embodiments, constructions andalternative forms are contemplated by the present invention as will fall within the scope of the appended claims.

In the drawings, 10 represents the barrel of a pneumatic hammer having an internally fixed guide sleeve 11. closing the bore 12 at the nose or forward end of the barrel.- 'VVithin the cylindrical bore 120i the barrel a piston (not shown) is reciprocal. The guide Serial No. 29,644.

sleeve 11 is suitably shaped internally to receive a rivet set orother tool generally indicated by the numeral 13; In the present instance the end of the'tool 13 when in serted in the sleeve is cylindrical in the forward end of the sleeve 11 and hexagonal toward the rear, the rear-end of the tool projecting beyond the sleevell for receiving a blow from the piston. A suitable enlarged portion 14 is provided on the'tool preferably as an annular rib or flange about the tool near the end of the sleeve 11. A projecting portion is also formed on the nose of the barrel 10 preferably as an annular flangeor rib which may be removable, and .1n the, present instance is const1tuted by a split ring 15 set into a suitable channeled recess theretor 1n the barrel 10. The retaining device in the present instance comprises a clip mounted on the nose of the hammer,

which clip has fingers underlying the rib 14 to engage the same by cooperation therewith. In the present instance. the fingers are provided by a Ushaped band 16, being so shaped to permit removal laterally away from the tool 13 which is normally encom-- passed by the U. The U-ban'd 16 is made integral with suitable side supporting means at right angles therewith extending longitudinally of the hammer in the form of strips 17 in the present instance, being spaced apart to lie on opposite sides of the nose. The rear ends of the side strips 17ihave'arcuate-edged flat flanges 18 extending inwardly toward the sides of thebarrel 10 and adapted to register circumferentially therewith, the two flanges preferably lying in the same plane. A heavy coiled spring 19 is interposedbetween the arcuate-odged flanges 18 and split ring 15 on the barrel. 'The spring 19 has a,

diameter such that it loosely encompasses the barrel 10 and such that it will lie between the opposite side strips 17 of the retaining clip. The upper coil or turn 20 is preferably ground to present a flat seat 21-for the 7 two arcuate flanges 18. Likewise the lower coil or turn 22 of the spring 19 is ground to form a flat seat 23 upon the ring 15.

The effect of the spring 19 is to move the retainerrearwardly of the hammer, but it is desirable to have the active retaining fingers or band 16 disposed forward of the end of the hammer so as to permit of some motion of the tool without engaging the retainingfingers. V

In'order to position the retaining-clip for this Fig. 1, and stop means is provided between.

. the clip and the barrel to position the clip by limiting rearward motion under influence oi the spring. This is accomplished by providing an abutting engagementbetween the re t ainer clip and the barrel 10. In the present instance this is accomplished by having the forward portions of the side strips 17 ofi'set inwardly of the clip providing stop shoulders 24 in the side strips 1? which shoulders engage the forward end of the barrel 10 as indicated at 25. p y

The provision of this type of retaining clip and the mounting means therefor makesthe same particularly advantageous. The spring 19 having the two end turns forming parallel seats 21 and 23 in the normal position of the device as shown in Fig.1, keeps the retaining sides" 17 normally parallel with the tool. Hence, the fingers 16- are properly positioned to engage the rivet set flange 14.. hen the tool isheld free from the work and operated, as in withdrawal, the impulse of? the hammer drives the tool forward and the flange and fingers engage moving the clip iforwardly with the tool, the clip cushioning the blow against the spring 19. In order to remove the tool the retaining clip may be forced laterally with aswdnging motion relat ve to the barrel thus compressing the spring on one side only as shown in. 2. Thislateral swinging movement 1s sediment to bring the U-band 16 out of engaging position with the flange 14 on the tool, thus permitting the latter to be removed from the sleeve 11. In Fig. 2 the flange ltis shownbelow the top edge of the band 16. Notonly the spring 19 but also the resiliencyof the clip itselt normally holds it parallel with the hammer barrel. This is,

of course, duetothe engaging of the barrel 1 sides by the arcnate edges of the flanges 18.

i the device.

The retaining clip thus ,neednot be removed from the hammer to eileet removal of the tool and no part of the retaining device need be loosened or unclamped.

sired. Because of its particular shape as shown in Fig. it is readily made of stamped sheet metal and may be provided for the tool as a renewable'part. t

It will thus be seenthat by. the above construction I have provided a thoroughly prac tical retaining device for tools in pnenniatic hammers and the like comprising an inertpensive retaining clip and a simplemonnting means therefor; and further adevice which is-readily operable for removal from the tool without removing or demount-ing any part of I claim as my'invent-ion: p 1. Atool retaining device for pneumatic hammers and the like comprising, in combination with the hammer and the tool, an annular rib at the forward end of'the hammer,

flange, supporting strips for saidretaining member on oppositesides of the hammer, said strips having a portion thereof abuttin the end of the hammer and another ortion t ere oi, lying alon side. the barrel 0' the hammer, flat arcuate-e .edfi anges on said strips ex'- tending inwar y toward. the hammer, and a coiled spring compressedbetween said? flan es and the riblof the hammer within; the side strips. i

. 2. A tool retaining device for pneumatic nation with the hammer and thetool', a, coiled .hammers and the like comprising, in coniloi tary member mounted on said hammer for rearward motionwith respect theretoby said sprin said member having two opposite 1 sides ying alongside the hammer and having portions adapted to limit the rearward motion of the member with respect to the hammer by engagement therewith, said. sides being-joined bya U-shaped ortion, sa .idunitarv member having parts t lereon to engage the tool in the forward motion thereof,

said sides having arcnate-edg ed flanges encompassing the. hammer and engaging with the coiled spring to effect the IEEIWQIYCLIHDL tion of the unitary member against the ing portions thereof. p 3. A tool retaining clip for pneumatic m ers and the like comprlsin in combination, a .U-shaped portion adaptefi tool,two opposite side stripsextending at right angles to said portion from the sides of the U, and inwardly extendincv flanges at the ends of said side strips, said es bein substantially. parallel with the shapeb member to embrace the and having elongated arcuateedges to engage with the sides of thehammer barrel to a resist displacement of the clip from saidhagn- 0n theotherhand, the retaining clip may be'easily removed from the barrel when dearms extending alongside of the barrel of the hammer, thebase ofthe U-shaped member ingv itself U-shaped at right angles to the.

4. A retaining clip for pneumatic I: and the like comprising a U-shaj dmember of somewhat resilient material f-aving two ly pressed against opposite sides of the barrel,

said arcuate surfaces being of a length to encompass the major portion of a the circumferonce ofthe barrel so that lateral motion of the clip with respect to the barrel about the eneompassing surfaces as a pivot causes sepa- 1,693,872 r p r 3 ration of the arms of the U against the reand having a pair'of parts resiliently engagsiliency of the member to permit removal of ing diametrically opposed arcuate portions 10 the clip from said hammer. of said hammer yieldingly to maintain said 5. A device of the character described havclip on said hammer.

' 5 ing, in combination with a power hammer In testimony whereof, I have hereunto afand a tool positioned thereon, a tool retaining fixed my signature. clip formed from a single piece ofsheet metal I having a part adapte to embrace said tool ERNEST H. SHAFF. 

